Lewis has shown himself to be abysmally ignorant of both the history and nature of stand-up comedy.
The point he seems to be trying to make--that today's comedy is morally inferior and a step backward from the humor of the past--is supported neither by the facts nor by the internal logic of his article.
One line that he uses to illustrate the "now comedy" ("If a gay person is sentenced to prison, is it really punishment?") was actually authored by Lenny Bruce, the spiritual father of the social-consciousness-raising humor that Lewis claims to eulogize.
Lewis then gives us W.C. Fields ("Anyone who hates children and dog's can't be all bad") as an example of someone whose barbs were always vented at "deserving targets." Does he mean to tell us that children and dogs are deserving targets? The fact is that Fields was a hostile man--a true misogynist--and that is why he was so funny.